Like others, the industry is pressured to do more with less because of shrinking tax revenues and limited grant program availability over the last decade. Yet public safety agencies are expanding their service offerings and providing better and faster emergency response because the mission matters. In many instances it is advanced technologies that are enabling emergency response entities to meet this challenge.
This is particularly true in the thousands of public safety answering points (PSAPs), which handle the nation’s 911 emergency calls. A PSAP is staffed by telecommunicators, or call-takers, who have been trained to field calls from the public and gather information related to an emergency situation. Telecommunicators also dispatch first responders to the emergency, including law enforcement, fire and emergency medical services (EMS). Dispatch operations entail taking the information received from the 911 call regarding the emergency situation and appropriately coordinating activity among the various first responders. Sometimes PSAPs are organized to segregate the dispatching of emergency services into dedicated groups corresponding to law enforcement, fire and EMS.
Across the U.S., thousands of PSAPs are preparing for or implementing Emergency Services Internet Protocol Networks (ESInets) not only to improve their level of service to the citizenry, but also to enhance their resiliency and redundancy. ESInets are thought to be the critical first step toward next-generation 911. These networks are broadband-enabled supporting the transmission of video, images and other bandwidth-intensive data files that would choke narrowband systems. ESInets enable the sharing of emergency data between PSAPs, expanding the possibilities of collaborative emergency response across the nation.
What Is an ESInet?
The reliability and speeds of telecommunication networks continue to increase. At the same time, the cost of network deployment continues to decrease. This is creating opportunities to establish larger geographical coverage areas while maintaining a “public safety grade” of service, as defined by the National Public Safety Telecommunications Council.
An ESInet is a standards-based “network of networks” that’s designed with a high level of redundancy and resiliency to ensure that the network can continue to operate (deliver 911 calls) even if some of the circuits or end points are no longer functioning.
The technology used in a PSAP is expensive compared with the equipment used in a corporate communications network. This premium is primarily because of the high degree of redundancy and expected public-safety level of performance the equipment must provide. In a small two-position PSAP, the population served by the facility may not be able to financially support the procurement and maintenance of this sophisticated equipment. Nevertheless, the community deserves the same level of emergency response as a large city. Partnering with other PSAPs on a regional or even statewide basis will bring advanced emergency response capabilities to communities that otherwise would be unattainable. An ESInet makes such collaborations possible.
At a two-position PSAP, a 50 percent workforce reduction would occur if one of the telecommunicators was unable to report, which could have a significant impact on the call center’s ability to provide emergency response services. However, if a geo-diverse ESInet was in place, the overflow call volume could be seamlessly transferred in real time to one or more 911 centers whose telecommunicators have been trained to handle calls from another location. In fact, a PSAP’s entire operations could be transferred via an ESInet to another 911 center when necessitated by localized disasters or long-term network/power outages.
In addition, ESInets make possible the virtual consolidation of PSAPs, whereby multiple 911 centers are combined via network connectivity and shared resources to service a broader area. There are numerous benefits to such an approach. One is greater consistency in terms of how emergency calls are handled throughout the region. Another is that smaller communities will receive the same level of service that larger communities with greater resources receive.
ESInet Options
Connectivity between PSAPs that share information over an ESInet generally is achieved by leveraging either a meshed network topology or multiple network rings, both of which provide more than one path to connect to other sites should a link go down.
Meanwhile, communication over an ESInet has been moving toward a common encapsulation protocol known as multiprotocol label switching (MPLS). MPLS is a scalable, protocol-independent transport technology that directs data between network nodes based on an assigned label, rather than a network address. This is a unique protocol that does not fall accurately into either the Open Systems Interconnection Layer 2 or Layer 3 model, but rather in between. With no packet inspection or address look-ups in routing tables, MPLS is a faster transmission protocol. Unlike traditional OSI Layer 2 data link protocols, MPLS operates with multiple paths of a ring active at the same time. This eliminates network reconfiguration times and shares the traffic load with all available ESInet paths.
The physical connection that transports the data can be almost any media — electrical, light or radio wave, or a mix of technologies on the same ESInet. This flexibility gives the network designer the ability to tailor the solution to best fit the application. The most common physical connections are leased-line private circuits, microwave links or fiber-optic cables.
Leased-line private circuits, which are very common in traditional corporate networks are “rented” from a telecommunications provider and used to connect two nodes on the ESInet at a specific bandwidth. These circuits can be leased in a variety of sizes, from a single T1 (1.54 Mbps) to multiple T1s bound together to increase bandwidth. The monthly local loop costs for locations in and around major cities will range between $300 and $500, while the costs in more remote locations may be two to three times higher. Bonded T1 loop charges are typically a multiple of the single T1 costs, with some discount for an underlying number of T1s.
DS3 monthly local loop costs range from $2,000 to $6,000 per month. (A DS3 has 28 times the bandwidth capacity of a T1 circuit at 45 Mbps.) Here again locations in major cities and their surrounding suburbs will see average local loop costs that are lower than in rural areas, in the $2,000 to $2,500 per month range. Ethernet also is becoming an attractive option for local loop access to MPLS networks (speeds range between 10 Mbps and 100 Mbps). Ethernet local loops typically are priced individually due to greater distance sensitivity, but may range from $3,000 to $10,000 per month per gigabit of bandwidth.
Microwave links have a high cost to design and establish, but have a lower monthly recurring cost for the life of the equipment. There are requirements regarding line of sight, height from the ground, FCC licensing and transmission speed.
High Bandwidth
Fiber-optic cable provides a pathway that offers advanced electronics that deliver very high bandwidth and thus very high transmission speeds over greater distances compared with the other transmission platforms, but this is a very expensive option. Construction costs for fiber-optic cabling can range from $30,000 to $80,000 per mile depending on the environment. In addition to the fiber cable itself, much of the construction cost is based on permitting and pathway construction.
There are two types of fiber: dark and lit. Dark fiber is just the fiber alone. The PSAP is expected to provide its own network electronics with the appropriate optical ports, which is what is needed to construct a fiber cabling plant. The capital cost for electronics to connect dark fiber can be as high as $250,000 per circuit.
Lit fiber is actually a data circuit, usually with a data transmission speed of 1 Gbps or 10 Gbps. Like a leased line, lit fiber is handed off at each end point as an Ethernet connection. You do not need long-distance optics and are not responsible for the “magic” that happens between nodes. The capital cost for electronics to connect lit fiber can be as high as $210,000 per circuit.
The lack of responsibility for the intermediate components of the fiber network may be of concern to a PSAP, which needs a public safety grade of service from the network. Whenever possible you should always contract with a service-level agreement that will give assurances that the circuit is monitored for troubles, and when there is trouble it will be repaired in a timely manner.
An ESInet provides the foundation for next-generation 911 services, which will exponentially enhance the emergency services provided by PSAPs. Such networks enable the transmission of very large data files, like video, the sharing of data between PSAPs, and the transfer of operations to other 911 centers when circumstances warrant. However, network design is quite involved and requires a team with a diverse set of skills, from network and radio engineers, to procurement and contracting specialists, to construction and project managers.
Building an ESInet does not have to be done all at once, but it should be accomplished with an eye toward the future. The electronics should be purchased with adequate capacity, in terms of slots and processor power, to allow for incremental growth as the facility expands its applications. Also good advanced planning of the equipment room or data center (grounding, cooling, power, security) that will house the equipment will provide a longer life of uninterrupted service.
As consolidations, migrations and system upgrades are being considered, ESInets become a cost-effective, long-term tool to serve the PSAP’s mission.
Jeff Lupinacci is a project manager/technology specialist with Mission Critical Partners, a public safety communications consulting firm headquartered in Port Matilda, Pa. He can be reached at jefflupinacci@mcp911.com.
